Question: which class IA flammable liquid with the lowest ceiling exposure whose instance of is occupational carcinogen?
Paraphrase: What is the IA class flammable liquid with the lowest ceiling explosure whose instance of is occupational carcinogen?
SPARQL (Wikidata): select ?ent where { ?ent wdt:P31 wd:Q21009053 . ?ent wdt:P2405 ?obj . ?ent wdt:P31 wd:Q21074597} ORDER BY ASC(?obj)LIMIT 5 
Answer: acetaldehyde, 1,1-dichloroethene, propylene oxide